1. Field of the Invention
The present invention relates to a fluid pump suitable for circulating a working fluid in a Rankine cycle system etc. and to a Rankine cycle system using that fluid pump.
2. Description of the Related Art
In the past, to utilize water or another working fluid to generate mechanical energy in a Rankine cycle system, the working fluid is heated using a boiler or superheater to generate high pressure steam and that generated high pressure steam is used to drive a turbine or piston for generating energy. Further, the steam utilized for driving these is liquefied by recovery at a steam condenser etc. and the liquefied working fluid is again fed to a boiler utilizing a fluid pump so as to recirculate the working fluid inside the system (for example, see Japanese Patent Publication (A) No. 2003-97222 and Japanese Patent Publication (A) No. 2003-161101).
However, in a conventional Rankine cycle system, as the fluid pump for circulating the working fluid, usually an electrically driven electrical pump is used. For this reason, a conventional Rankine cycle system is required to be provided with a drive circuit for driving this electrical pump, a power circuit for supplying power, etc. The configuration of the equipment therefore becomes complicated and an increase in cost is invited.